1 Samuel 17:55-58

55Now as Saul watched David going out to fight the Philistine, he asked Abner, the general in command of the army, “Whose son is this young man, Abner?” Abner replied, “As surely as you live, O king, I don’t know.”

56The king said, “Find out whose son this boy is!”

57So when David returned from striking down the Philistine, Abner took him and brought him before Saul. He still had the head of the Philistine in his hand.

58Saul said to him, “Whose son are you, young man?” David replied, “I am the son of your servant Jesse in Bethlehem.”